Metal strip such as that used in roll-up awnings



Dec. 12, 1961 H. NELSON 3,012,318

METAL STRIP SUCH AS THAT USED IN ROLL-UP AWNINGS Filed Dec. 22, 1955 /A/n/fA/TOR: f/,qme Y NEL s cw,

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United States Patent Olice 3,012,318 METAL STRIP SUCH AS THAT USED IN ROLL-UP AWNINGS Harry Nelson, McKeesport, Pa., assignor to Artcraft Venetian Blind Manufacturing Company of St. Louis, St. Louis, Mo., a corporation of Missouri Filed Dec. 22, 1955, Ser. No. 554,739

1 Claim. (Cl. 29-528) The present invention relates to a metal slat such as that used for awnings, and to a method of making the same.

Heretofore, slats of this type have been sheared from longer strips, into lengths suitable for the usage to which they are put. Necessarily, they are of very thin material, particularly if they be used for draw-up or roll-up awmngs.

In the past, it has been disadvantageous to use steel for such awnings because at the ends of the slats, where they have been sheared, there is inadequate weather protection. Any coating process, such as galvanizing, is absent from the sheared end edges, and, in view of the thinness of these edges, it is diicult to obtain an enamel or other paint or lacquer coating that will adhere, or that will survive the normal weathering, flexing and impacts.

Additionally, the thin steel slats are apt to be subjected to such forces, from time to time, as will bend or twist their ends. Since they may be in the order of .015 inch or less cold-rolled strip, they are fairly easily bent, even when they are formed into a curved cross section-i. e., a section that is non-planar.

The present invention overcomes both of these problems. It provides a method of making a slat, and provides a new Slat, with end edges that have the galvanization, and which are Superior insofar as their ability to hold paint and such coatings is concerned. They are also stronger and more rigid in resisting deformations. Other advantages -will appear from the description to follow.

In the drawings:

FIGURE 1 shows a steel strip as it comes from a roll prior to enameling;

FIGURE 2 is a view of the strip cut from the roll and enameled;

FIGURE 3 is a transverse section on a line 3 3, the view being full size;

FIGURE 4 is a section on the line 4 4 of FIGURE 2;

FIGURE 5 is an enlarged view of one end of the strip showing the fold-over; Y

FIGURE 6 is a broken view of the strip somewhat enlarged but shown after it has been through the forming die;

FIGURE 7 is an enlarged transverse line 7 7 of FIGURE 6; and

FIGURE 8 is a longitudinal section 8 8 of FIGURE 6.

FIGURE 1 shows the initial strip 1G severed from a longer supply of strip material indicated by the dash lines. The strip 10 is, in the preferred form, made of metal such as steel, having an integral protective coating such as a galvanized plating 11. For practical reasons, it is necessary to galvanize the supply strip material prior to severance of the strips 10. However, this means that the extreme end edges 12 and 13 are unprotected.

Heretofore, it has been the practice to enamel the strip, or slats; and such enameling supplies protection to the raw end edges. But the ends are subjected to weather, or to bumping and the like, as well as to being ilexed to some extent, ywith the result that the enamel or section on the along the line 3,012,318 Patented Dec. 12, 1961 applied coating is fractured on part or all -ofthe end edges, leaving them subject to corrosion. Y

In the present invention, the galvanized strip I10 is initially cut slightly longer than the length required. Then, as shown in FIGURE 2, the strip 10 is coated, as by an enamel coating 15, which adds protection and beauty, the enamel covering the entire strip including the end edges LZ and 13.

The enameled strip is then subjected to a bending operation that folds its ends 16 and 17 over to lie flatly and closely against the adjacent parts of the strip 10. In the bending operation, if appropriate care is taken, the enamel is not damaged, and it normally is elastic enough to stretch around the new end edges 18 and '19, it being noted that these edges are rounded rather than sharp as are the edges 12 and 13 provided by the single thickness of metal. Consequently, the enamel is less likely to be chipped olf. A suitable machine for performing the bending is shown in applicants pending application, Serial No. 534,418, tiled September 14, 1955, under the title of Apparatus For Cutting And Bending Strip Material, now Patent No. 2,963,066.

The galvanized coating 11 is elastic enough to coat the edges 18 and 19 so that, even if the enamel is knocked olf in use, the end edges remain protected.

The original end edges 12 and 13 are folded back to where they are well protected from blows and from the weather. Normally, they are turned back on the underside of the awning or ylike article, so as to be sheltered from the weather and from moving objects such as branches, or leaves, yor other things. Therefore, corrosion is less likely -to reach them, and less likely to gain any foothold because the enamel is much more likely to stay on to cover the edges 12 and 13. Yet the foldedover ends do not overlap uncoated surfaces, because the infolded surfaces between the folded-back ends and the body of the slat are both galvanized and enameled.

Additionally, the ilexing of the ends of slats of awnings, by blows, or weather, or rolling them up and down, lis substantially reduced by having the double thickness of metal at the ends. This not only adds to the durability of the coatings, but also adds life to the awnings themselves.

The invention has been described with particular reference to a strip steel Slat for roll-up awnings, having a galvanized coating and an enamel covering. The invention is valuable on strips or slats used for other articles, of which blinds are an example. The base material may be varied, but it will be understood that the full value of the invention is gained only where the base material is subject to corrosion, and where the initial coating does not cover the end edges 12 and 13, and the added covering may not remain on these edges under conditions of more or less severe use. Other corrodible metals than steel may be used, and other coatings than galvanizing may be used. And while enameling has been described as the outer coating, it is subject to variation. Typical outside coatings are paints and lacquers, although enamel is usually best for rol-l-up awnings of steel slats.

What is claimed is:

Av method of making thin, metal strips for use in window coverings or the like; comprising applying a protective, metallic film coating to elongated strip material of greater length than the ultimate strips to be made, applying a ilm coaing of enamel yor the like to the unsevered strip; severing a strip of desired length from the elongated strip material, then bending the coated end tips of the strip back to overlie and rest snugly against the adjacent parts of the strip, so as to provide ends having a total thickness only that of the thicknesses of the layers of coated metal and the lm coatings, and

nally transversely curving the strip, including the ends 876,593 Rush Ilan. 14, 1908 having the turned-back endrtips. v 1,2732358 Gravell July 23, 1918 1,386,033 Simon Aug. 2, 1921 v References Cited in the file, of this patent 1,539,328 Richards May 26, 1925 '5 l1,949,653 Moore Mar. 6, 1934 UNITED STATES PATENTS 2,159,002 Ashmore May 23, 1939 6415237 Ru'ssell Ian. 9V, 1900 2,566,138 Osterheld Aug. 28, 1951 

